Stack several time the same channel?
Using drivers, you can use a channel as input value for almost everything you want to animate.

To keep it simple, I've used only two objects: the location X channel of the Sphere will be applied to the location X channel of the Cube



In this example, I've added drivers to the Cube location, (move the cursor over the location fields then press d)

In the Graph Editor, switch to Drivers Mode



Select the channel you want to animate, then set the Drivers properties in the Properties Panel (n)

If you only need to copy the channel without any operations, you can set type="Averaged Value".
Otherwise, you can choose the type you need: